Clinical pharmacology: the science of therapeutics

Clinical pharmacology: a paradigm for individualized medicine

Individualized medicine provides a powerful engine revolutionizing the practice of clinical pharmacology, tailoring genetic and molecular profiles of patients to improve therapeutic specificity, reduce treatment variability and minimize adverse drug events. In that context, advances in individualized medicine have transformed the science of clinical pharmacology and therapeutics from drug discovery through identification of drugable targets, development through stratification of disease risk, regulation through identifying pathways mediating off-target effects and utilization through personalizing drug regimens. This revolution in fundamental and applied therapeutics has entrained an evolution in biology and medicine. Insights in the mechanistic basis of cell, tissue and organ function, and their interface with the environment are being translated to define disease risk, identify processes mediating disease susceptibility, target mechanism-based therapies, and tailor prevention and control paradigms, providing previously unanticipated opportunities for patient-specific disease management. The emerging field of individualized medicine is transforming the practice of clinical pharmacology, driving the leading edge of discovery from the laboratory bench to the evidence basis of practice in the clinic, extending to populations, to transform healthcare and create predictive, personalized and pre-emptive solutions for tailored patient-specific therapeutic strategies.

Development of a therapeutics curriculum to enhance knowledge of fourth-year medical students about clinical uses and adverse effects of drugs

BACKGROUND

Enhanced clinical pharmacology and therapeutics education of medical students is important for improving effective and safe drug therapy. Increased education about pharmacovigilance is needed because serious drug-induced adverse effects are increasing. Fostering the needed scientific approach to prescribing requires knowledge of evidence-based drug therapy, based on understanding clinical trials. Therapeutic agents with novel mechanisms of action are increasingly available, and an unbiased understanding of the risks and benefits of novel agents is also important. These issues can be addressed in clinical pharmacology courses. However, many medical schools lack sufficient clinical pharmacologists to teach such courses. The Southern Illinois University Medical School faculty implemented an Advanced Therapeutics course to address these issues.

DESCRIPTION

Development of this course involved defining appropriate content and organizing preclinical pharmacology and clinical faculty into teaching teams. The course was offered to 4th-year medical students and covered clinical trial information, and cutting-edge therapeutic developments. The "ABCs of Pharmacology" is a mental algorithm that was presented in the sophomore year and reintroduced in this course. This algorithm emphasizes pharmacovigilance, which stresses the balance between positive and negative effects of pharmacological agents. General principles of clinical pharmacology and therapeutics were covered by a clinical pharmacologist. Most sessions on specific disease treatment involved an integrated presentation by a preclinical pharmacologist and a clinician with expertise in that topic, often in the context of clinical cases. Other important topics were emphasized, which reinforce individualization of therapy, including pharmacogenomics that may determine idiosyncratic responses. Feedback during and following the course was obtained via questionnaires.

EVALUATION

This approach was well received by participating students and graduates. Most students rated this course as a valuable experience.

CONCLUSION

This approach appears useful for educating medical students about therapeutics at medical schools that lack sufficient clinical pharmacology faculty to mount such a course.

Association of GUCY2C expression in lymph nodes with time to recurrence and disease-free survival in pN0 colorectal cancer

CONTEXT

The established relationship between lymph node metastasis and prognosis in colorectal cancer suggests that recurrence in 25% of patients with lymph nodes free of tumor cells by histopathology (pN0) reflects the presence of occult metastases. Guanylyl cyclase 2C (GUCY2C) is a marker expressed by colorectal tumors that could reveal occult metastases in lymph nodes and better estimate recurrence risk.

OBJECTIVE

To examine the association of occult lymph node metastases detected by quantifying GUCY2C messenger RNA, using the reverse transcriptase-polymerase chain reaction, with recurrence and survival in patients with colorectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

Prospective study of 257 patients with pN0 colorectal cancer enrolled between March 2002 and June 2007 at 9 US and Canadian centers (7 academic medical centers and 2 community hospitals) provided 2570 fresh lymph nodes measuring 5 mm or larger for histopathology and GUCY2C messenger RNA analysis. Patients were followed up for a median of 24 months (range, 2-63 months) for disease recurrence or death.

MAIN OUTCOME MEASURES

Time to recurrence (primary outcome) and disease-free survival (secondary outcome) relative to expression of GUCY2C in lymph nodes.

RESULTS

Thirty-two patients (12.5%) had lymph nodes negative for GUCY2C (pN0 [mol-]), and all but 2 remained free of disease during follow-up (recurrence rate, 6.3%; 95% confidence interval [CI], 0.8%-20.8%). Conversely, 225 patients (87.5%) had lymph nodes positive for GUCY2C (pN0 [mol+]), and 47 developed recurrent disease (20.9%; 95% CI, 15.8%-26.8%) (P = .006). Multivariate analyses revealed that GUCY2C in lymph nodes was an independent marker of prognosis. Patients who were pN0 (mol+) exhibited earlier time to recurrence (adjusted hazard ratio, 4.66; 95% CI, 1.11-19.57; P = .04) and reduced disease-free survival (adjusted hazard ratio, 3.27; 95% CI, 1.15-9.29; P = .03).

CONCLUSION

Expression of GUCY2C in histologically negative lymph nodes appears to be independently associated with time to recurrence and disease-free survival in patients with pN0 colorectal cancer.

An independent contribution to the growth of paediatric clinical pharmacology in Italy

OBJECTIVE

Providing young researchers with an education is one of the priorities of the Mario Negri Institute, the main, private, non-profit Italian research foundation.

INTRODUCTION

Between 1994 and 2006, 21 research fellows from different health-care areas were selected for a problem-oriented fellowship in paediatric clinical pharmacology in the Laboratory of Mother and Child Health. Of these, 18 received at least 2 years of training and 12 completed a formal pharmacology research course focused on paediatrics. One research fellow received a PhD degree, and another is currently working towards a PhD. The majority of these research fellows are currently employed in the private health sector, four work in the public National Health Service, and four continue to work as senior scientists at the Mario Negri Institute.

DISCUSSION

To guarantee a safer and more effective use of medicines in children, more post-doctoral fellows should receive training in paediatric clinical pharmacology. Financial resources must be raised to support an adequate education, training, and research programme in this field. A possible challenge could be a European network of interested, expert institutions collaborating in a joint initiative in the interest of paediatric clinical pharmacology, and, more importantly, in the interest of rational therapies for children.

K(ATP) channel pharmacogenomics: from bench to bedside

Inheritance plays a significant role in defining drug response and toxicity. Advances in molecular pharmacology and modern genomics emphasize genetic variation in dictating inter-individual pharmacokinetics and pharmacodynamics. A case in point is the homeostatic ATP-sensitive potassium (K(ATP)) channel, an established drug target that adjusts membrane excitability to match cellular energetic demand. There is an increased recognition that genetic variability of the K(ATP) channel impacts therapeutic decision-making in human disease.